Professor Chun Ning (Jeanie) Lau
Physics Department
University of California, Riverside

 

Phase Coherent Charge Transport in Graphene, Carbon Nanotubes and Molecular Nanostructures

The electronic properties of a conductor are altered profoundly when one or more of its dimensions are miniaturized to nanometer in scale. In this talk I will discuss quantum transport in 2D and 1D nanostructures, in particular, graphene, carbon nanotubes and molecule-based junctions. I will first focus on ballistic transport of electrons and holes in graphene. We demonstrate that graphene can act as a quantum billiard, where interference of multiply-reflected charge waves gives rise to conductance oscillations. When graphene and carbon nanotubes are coupled to superconducting electrodes, they form novel Josephson junctions and give rise to enhanced conductance at zero-bias, multiple Andreev reflections, and gate-tunable switching current. Finally, I will discuss pressure-modulated microscopy of switching centers in metal/molecular monolayer/metal heterojunctions, which reveals quantum coherence of electrons at room temperature.